Treatment of hospitalized patients frequently involves control of one or more physiological parameters in concert with administration of fluids, pharmaceuticals, and nutrition through intravenous (IV) infusion pumps. Current systems rely on intervention by clinicians who manually adjust infusion rates on the basis of monitored variables and “paper” protocols, which are derived from experience and/or evidence as may be presented through medical literature.
However, a manual control (or titration) process is burdensome to care providers and may not achieve optimal care for a patient. In part, this is due to complexity of the physiological control problem, limited resources available to monitor patient status, and the static nature of adjustment protocols. Manual intervention also provides opportunities for introduction of medication errors during calculation, data entry, or IV pump programming, for example. In addition, paper protocols and/or nomograms used by a bedside nurse may be necessarily simple and may be unable to compensate for a wide variety of patient drug sensitivities, nonlinear drug response characteristics, and dynamic nature through time.
As one example of a condition that requires treatment possibly using manual intervention, hyperglycemia or high blood sugar is a condition in which an excessive amount of glucose circulates in blood plasma. Pronounced hyperglycemia occurs in approximately 75% of acutely ill patients and is associated with a significant increase in morbidity and mortality. Studies have shown that maintaining normal blood glucose levels through intravenous (IV) infusion of insulin can lead to improved outcomes in acutely ill patients. Thus, treatment of hyperglycemia requires elimination of an underlying cause if possible, e.g., treatment of diabetes when diabetes is the cause, and in most cases, direct administration of insulin is used, under medical supervision. However, current clinical practices for treating hyperglycemia that involve intensive insulin therapy are a burdensome activity that involve frequent (1-2 hour) blood glucose measurements followed by manual adjustment of an IV insulin infusion rate. Changes to insulin infusion are directed by protocols that can fail to adequately represent patient-to-patient differences and present a high risk of hypoglycemia. Thus, manual supervision by medical personnel can increase chances of human error and often does not consider specific patient responses to a drug therapy.